Sen. Jon Tester, a liberal Democrat, is attempting to hold off Republican challenger Rep. Denny Rehberg in a tight Montana Senate race. Rehberg is a Power Line Pick Six candidate. For Republicans to gain control of the Senate, they almost certainly need to win this race.

Tester has been highly unconvincing in his belated attempts to convince Montana voters that he’s not in the pocket of the Obama administration on all the big issues. In a two way race with Rehberg, Tester would likely be toast.

However, there’s a third candidate in Montana — Dan Cox of the Libertarian Party. Cox has not polled particularly well, and third party candidates tend to underperform their polling when election day rolls around. Few voters are foolish enough, when push comes to shove, to waste their vote on a no-hoper.

However, Cox is now receiving help from Tester supporters. As the Billings Gazette reports, a group that calls itself the Montana Hunters and Anglers Leadership Fund has spent nearly $500,000 to run an ad attacking Rehberg. It also spent $40,000 on web ads and $146,000 in anti-Rehberg mailings.

Behind the Montana Hunters and Anglers Leadership Fund stands the League of Conservation Voters, an environmental group that supports Tester, not Cox. Moreover, the actual money being used to bolster Cox is coming from leading Montana Democrats. The Daily Caller has identified these Democrats as:

Land Tawney, the outfit’s president, a member of Montana Sportsmen for Obama who also serves on Tester’s Montana Sportsmen’s Advisory Panel. On July 28, 2011, he made a $500 donation to Tester.

Kendall Van Dyk, the group’s secretary, currently a Democratic state senator in Montana. He is also a member of Montana Sportsmen for Obama and, according to Federal Election Committee filings, he gave $200 to the Montana Democratic Party, though he has not donated money to Democrats in 2012.

Barrett Kaiser, treasurer of the group, the former chief of staff to Sen. Max Baucus, Montana’s senior senator and a Democrat. He made three separate donations to Montanans for Tester in 2011, totaling $2,350. He made two separate donations to the Montana Democratic Party in 2012, totaling $1,500. He has made several donations to both Tester and Baucus’ campaigns over the past several years.

George Cooper, the director of Montana Hunters and Anglers, a consulting firm official who made two donations to Tester in 2012, totaling $1,250. He has also donated $1,000 to the Democratic Senatorial Campaign Committee, as well as donating to Democratic Senators Kristin Gillibrand and Bill Nelson.

Senate races in Republican states like Missouri and Indiana have turned problematic for Republicans due to reasons that are well known. But Montana is an even more Republican state, and Denny Rehberg has not shot himself in the foot the way Todd Akin and Richard Mourdock arguably have. Republicans must do all we can to elect Rehberg.